Complex Heat Pipe And Two Phase Flow Of The Separated Type Heat Pipe Performance Experimental Research

Combined with the engineering practice background, experimental study on two kinds of propelling heat pipe is carried on. The propelling heat pipe has advantages over non-propelling separate heat pipe. The study on propelling heat pipe has guiding significance and application value to the design and application in the engineering practice.This paper introduces the general development situation and domestic recent development situation of heat pipe first, then structure and heat transfer characteristics of all kinds of heat pipe are analyzed, and complex heat pipe which is a kind of propelling heat pipe is presented. In this paper, further experimental study and the simple theory analysis on the complex heat pipe are done. The study shows that there is optimum value (0.38-0.43) about filling ratio in the complex heat pipe system. Large or small filling ratio has negative influence on heat transfer performance. Heat transfer quantity increases as working medium flow increases, and keeps constant as it comes to flow limit of working medium. The higher pipeline resistance is, the worse performance of the heat pipe is. The complex heat pipe system is started more easily on the condition that little loop emerges in the complex heat pipe system. As the little loop emerges, heat transfer quantity of the complex heat pipe system is improved by20%and28%in the working condition that the driving temperature difference is12.8℃and16.0℃.Based on the complex heat pipe, a new kind of propelling heat pipe with more simple structure is put forward---two-phase flow separate heat pipe. In this paper, further experimental study and the simple theory analysis on two-phase flow separate heat pipe are done. On condition that the two-phase flow separate heat pipe without liquid storage pot is started, heat transfer quantity falls as filling ratio increases. The emerging of gas-liquid two phase flow can improve heat transfer efficiency. Heat transfer quantity improved ranges from4%to21%as the emerging of gas-liquid two phase flow. Improving the water flow of cold/heat source is favorable to heat transfer performance. The requirement for startup of two phase flow separate heat pipe system is that pressure in the import of solution pump be not higher than that in the condenser. As a result of its good adaptability, the evaporator and condenser of two phase flow separate heat pipe can be installed in any relative position. In the two-phase separate heat pipe system with liquid storage pot, heat transfer quantity increases, reaches maximum and decreases as filling ratio increases, and optimum value of filling ratio is0.35. Maximum heat transfer quantity of the heat pipe system with liquid storage pot is8%larger than that of the heat pipe system without liquid storage pot.Propelling heat pipe is a technology that transfers high density energy via latent heat and low energy consumption, with the characteristic of energy saving, efficiency and controllability etc. Propelling heat pipes have the obvious advantage over non-propelling heat pipes on limit of mounting position of evaporator and condenser, insufficiency of the working medium driving force owing to distance, poor adaptability to variable working conditions.